1. Field of the Invention
The invention relates to an integrated optic device, for frequency up-conversion and phase shift control of high frequency signals.
2. Description of the Prior Art
An optical waveguide arrangement which operates in the manner of the interferometer to provide modulation and/or switching functions is known from U.S. Pat. No. 4,070,094. The theory, structure and fabrication method for optical waveguides integral with a substrate are known in the prior art and are referred to in the aforementioned U.S. Pat. No. 4,070,094 and the technical literature references in the specification of that patent. In that prior art structure, two optical waveguide branches having a common connection diverge along a substantially co-extensive distance, and reconverge to provide first and second light paths of identical optical length. Conductive electrodes are disposed contiguous to at least one of the optical waveguide branches and are connectable via a control switch to a source of electrical energy. In the absence of any electrical field, light energy entering the two branches propagates along identical optical path lengths and recombines constructively at the reconvergence of the branches. However, selectively applied electrical energy produces electrical fields in one or both of the branches to change the optical property of at least one of the branches, causing phase differences in the optical energy propagated in the branches, to produce at least partially destructive interference at the reconvergence of the two branches. Modulation is effected by varying the extent of the differences between the thus controlled optical properties of the two branches.